A1260603033uvncH

1

GROSS ANATOMY REVIEW

11/17/2006 By Raghu
Muppavarapu, Dmitry Goldin, and
Simon Abramson

2
How to STUDYfor EmbryoLangmans Blue
Boxes (clinical correlation)Langmans
Illustrations (captions!!)High Yield/BRSco-ops
lecture notes
3
INTRODUCTION OSTEOLOGY
BONES YOU SHOULD KNOW FOR THIS EXAM KNOW THESE
WELL THORACIC VERTEBRA, RIBS, CLAVICLE,
PELVIS BE FAMILIAR WITH EMPHASIZED ARTICULATIONS
AND GROOVES/ROUGHENINGS, POINTS Scapula,
Proximal Humerus, Proximal Femur, Few Points on
Posterior Skull
4
Primary Curvature of the vertebral column
refers to the concave curvature of the embryo.
During early life (e.g. by starting to walk on
two limbs), secondary, convex curvatures
develop. Namely- of the cervical vertebra and
lumbar vertebra.
5
LORDOSIS (Left) refers to increased Lumbar
curvature (e.g. more concavity) due to muscular
weakness or osteomalacia. KYPHOSIS (far Right)
refers to increased Thoracic curvature (e.g. more
concavity), often resulting from
osteoporosis. (Middle Picture is Normal)
6
SCOLIOSIS is a lateral deviation due to unequal
growth in the vertebral column, erosion of the
vertebral bodies, or asymmetric paralysis or
weakness of vertebral (e.g. deep back) muscles.
7
There are SEVEN cervical vertebra, TWELVE
thoracic vertebra, FIVE lumbar vertebra, FIVE
fused sacral vertebra (sacrum), and 3-4 fused
coccygeal vertebra (coccyx). Note that there
are 31 pairs of spinal nerves. From C1 to C7 they
exit through the intervertebral foramina ABOVE
their respective vertebra. Spinal nerve C8 exits
through the foramina BELOW C7 (because there is
NO CV8). Therefore, from the Thoracic Vertebra
downward, the respective spinal nerve exits
through the foramina BELOW the respective
vertebra. CV, TV, LV, SV, CoV refer to the BONY
VERTEBRA C, T, L, S, Co refers to the actual
SPINAL NERVES
Note that the spinal cord ends at LV2,
whereas the dural sac ends at SV2.
8
DORSAL (posterior) PRIMARY RAMI INNERVATE DEEP
BACK MUSCLES (EVERYTHING INTERNAL TO THE
THORACOLUMBAR FASCIA) The DORSAL CUTANEOUS
BRANCH ALSO SUPPLIES PART OF THE DERMATOME IN
THE BACK VENTRAL (anterior) PRIMARY RAMI
INNERVATE EVERYTHING ELSE (as far as youre
concerned... it is a bit more complex in head
and neck) MAKE NOTE OF the DORSAL ROOT GANGLION-
THE CELL BODIES OF THE SENSORY NEURONS THAT
LIVE HERE CORRESPOND TO THE DERMATOME OF THAT
SPINAL NERVE CANDY ?- DRG CELLS DERIVED
FROM WHICH EMBRYONIC CELL LINE?
9
Notice how the thoracic dermatomes follow the
curvature of the ribs!!
DERMATOMES YOU NEED TO KNOW NOW- S2,3,4-
Corresponds to the perineum L1- Corresponds to
the Mons Pubis in Females, provides somatic
innervation to the area over the inguinal
ligament T10- Umbilicus- Periumbilical pain is
the initial radiation of appendicitis, prior to
inflammation of parietal peritoneum T4- Nipples
are the landmark anteriorly T2- Radiation of
visceral heart pain, comes down from the thorax
to the medial side of the LEFT arm. The nerve
forming this part of the dermatome, which is the
LATERAL CUTANEOUS BRANCH OF THE T2 SPINAL NERVE.
It is has a special name on the left side
INTERCOSTOBRACHIAL NERVE. Candy ? Name two
structures/areas from which SOMATIC pain is
referred to the NECK and SHOULDER. BE
SPECIFIC!! Candy ? The CELL BODIES OF THE
SENSORY NEURONS INNERVATING THE HEART
VISCERA/PARENCHYMA ARE LOCATED WHERE? BE
SPECIFIC!!!
10
Heres the typical Thoracic Vertebra Note the
body. The pedicles run between the transverse
process and body. The laminae run between the
transverse processes and the spinous process. The
superior demifacet articulates with the head of
the corresponding rib (i.e. TV8 Eight rib),
while the inferior demifacet and articulates with
the head of the rib below. Note the TRANSVERSE
PROCESS, which articulates with the TUBERCLE OF
THE CORRESPONDING RIB. Like the other joints
mentioned here, it is synovial. The superior and
inferior articular processes articulate with the
inferior and superior articular processes of the
vertebra above, and below, respectively.
11
The body of the vertebra are lined by hyaline
cartilage. Between this and the bodies is a joint
(symphysis) consisting of an outer
fibrocartilaginous ring and an inner mucoid
substance, which are known as anulus fibrosus
and nucleus pulposus, respectively. A slipped
disk refers to a protrusion of the nucleus
pulposus through the anulus fibrosis and into
the intervertebral foramen or vertebral canal,
resulting in compression of spinal nerves, and
pain along the corresponding dermatome(s). Most
frequently, this occurs in the lumbar
region. Candy ? Nucleus pulposus is the
remnant of what embryonic structure?
12
Ribs 3-9 are the typical ribs, the structure of
which youre expected to know. These ribs have
two articular facets which articulate with the
vertebra above and below it. On the RIB, the
inferior articular facet is larger and
articulates with the superior articular facet of
the vertebra (which corresponds to its number).
The superior articular facet of the rib is
therefore smaller, and articulates with the
smaller inferior articular facet of the vertebra
below. Note AGAIN- the articular process of the
TUBERCLE which articulates with the TRANSVERSE
PROCESS of the corresponding vertebra.The angle
of the rib denotes the point at which it begins
to curve inferiorly. The inferiorly positioned
costal groove has the intercostal Vein, Arterior,
and Nerve (V.A.N. mneumonic) running on its
internal surface. Therefore, when one performs
any procedure requiring perforation of the
thoracic wall, STAYING AWAY FROM THE INFERIOR
MARGIN OF THE RIB ABOVE IS CRITICAL. Ribs 1-7
are true ribs because they articulate directly,
via their own costal cartilage with the sternum.
Ribs 8-12 are false ribs. Ribs 8-10 articulate
with the sternum indirectly via a common terminal
costal cartilage. Ribs 11 and 12 are floating
ribs and have to connection with the sternum. Rib
1 articulates with the manubrium as a
synchondrosis, thereby not allowing movement. The
other articulations with the sternum are synovial
plane-type joints and allow for movement. The
2nd rib articulates with both the manubrium and
body of the sternum, thereby allowing the sternal
angle of Louis (TV4/5) to act as its landmark.
Note the first rib- it is not palpable. It has a
groove anteriorly for the subclavian vein, and
posteriorly for the subclavian artery. It also
has a scalene tubercle for the anterior scalene
(dont worry about that one yet).
13
Clavicle- how to tell left from right The flat
end of the clavicle is lateral, while the
quadranglular end is medial. The lateral
curvature is concave from an anterior
perspective, while the medial curvature is
convex. There is an articular disk present on
the manubrium for the inferior portion of the
quadrangular head of the clavicle. The
sternoclavicular joint is synovial and classified
as a saddle joint, but it functions as a ball and
socket joint. The lateral surface articulates
with the acromion of the scapula (as a synovial
plane joint). Candy?- Need both answers- what
two-bellied muscle is attached superiorly to BOTH
the CLAVICLE AND THE STERNUM, and what is it
innervated by?
14
Look at the scapula, you will be MUCH more
familiar with it in the spring. For now, know
that the acromion articulates with the clavicle,
the coracoid process serves as an attachment for
pec. minor m., the medial border externally
serves as the attachment for the rhomboid mm.,
the superior angle serves as the attachment for
levator scapulae m., the deltoid attached to the
acromion, the trapezius m. attaches to the spine,
and most importantly.. the SERRATUS ANTERIOR M.
attaches to the MEDIAL BORDER of the SCAPULA
INTERNALLY.
15
The anatomical neck is between the smooth head,
which articulates with the glenoid fossa of the
scapula, and the shaft of the humerus. The
surgical neck, however, is the most likely place
of fracture in the proximal humerus. The pec.
major m. inserts on the lateral side of the
intertubercular groove, while the latissimus
dorsi inserts onto the floor of the
intertubercular groove (note the roughenings on
the diagram). (Mneumnoic Lady b/w two
majors-other major is teres major m.).
16
You need to know the pelvic bone (os coxae)
fairly well. Understand that the pelvis consists
of three fused bones- ischium, ilium, and pubis.
Be able to identify, the pubic tubercle, pubic
crest, inferior and superior pubic rami, the
pectineal line, the obturator foramen, the
arcuate line, the iliac fossa, the articular
surface for the sacrum (AURICULAR surface), the
ASIS, and the ischial spine. The acetabulum forms
an articular surface with the head of the femur.
The horizontal plane passing the top portion of
the iliac crest is the supracristal plane, it
occurs at LV4 and demarcates the bifurcation of
the abd. aorta into common iliac aa.The
horizontal plane passing through the tubercle of
the iliac crest is the intertubercular plane, it
occurs at LV5, and demarcates the junction of
common iliac veins to form the IVC.
17
The sacrum consists of 5 fused vertebrae. The
anterior posterior sacral foramina are
equivalent to intervertebral foramina (here-
anterior transmits ventral primary rami,
posterior transmits dorsal primary rami). The
coccyx is important in the pelvis because it acts
as a point of insertion for many of the levator
ani muscles. Know the SACRAL PROMONTORY, it is
the posterior border of the pelvic brim and
overlooks the pelvic cavity. The ala of the
sacrum forms a synovial joint with the pelvic
bone via an AURICULAR (ear-like) articular facet
that articulates with the AURICULAR articular
surface of the ilium (sacro-iliac joint). Because
the upper weight the body is transmitted through
this joint, back pain related to it is common.
The sacral hiatus, which is guarded by the sacral
cornu is used for introducing anesthesia.
18
The SACRAL PROMONTORY forms the SUPERIOR BORDER
OF THE PELVIC BRIM. The rest of the pubic brim
is formed by the pubic crest, pecten pubis, and
arcuate line, and pubic crest. The true pelvis
extends from the pelvic brim to the
pelvic diaphragm. The false pelvis extends from
the iliac crest to the pelvic brim and is
actually a part of the abdominal cavity. Candy
? What is the point of insertion of the Psoas
Minor M., if present. Be VERY specific. The
obturator membrane forms a fibrous joint- a
SYNDESMOSIS. The obturator canal transmits the
obturator neurovasculature. The
SACROSPINOUS LIGAMENT is a degenerated portion of
the COCCYGEUS M. (aka ischicoccygeus), and spans
from the ischial spine to the lower sacrum and
coccyx. The SACROTUBEROUS ligament spans from the
ISCHIAL TUBEROSITY and FANS OUT along THE SACRUM
AND AND COCCYX. These ligaments prevent upward
rotation of the sacrum, but most importantly
contribute to the formation of GREATER andLESSER
SCIATIC FORAMINA.
19
All you need to know for the femur is that the
greater trochanter is the site of insertion of
the piriformis m. and obturator internus m.,
while the Iliopsoas m. inserts onto the lesser
trochanter.
In the skull, the external occipital protuberance
and the superior nuchal line are a couple of the
sites of insertion for the trapezius m.
20
You should, at the least, know the following body
planes and vertebral levels CV6- Cricoid
Cartilage- Trachea and Esophagus start
here. TV4/5- Sternal Angle of Louis TV8- Caval
Hiatus TV10- Esophageal Hiatus TV12- Aortic
Hiatus TRANSPYLORIC PLANE- LV1 UPPER PART- CELIAC
TR. LOWER PART- SMA 2nd 4th part of duodenum-
LV2 SUBCOSTAL PLANE- LV3 3rd PART OF THE
DUODENUM, IMA TRANSUMBILICAL PLANE-
LV3/4 SUPRACRISTAL PLANE- LV4 Bifurcation of
abdominal aorta INTERTUBERCULAR PLANE
LV5-Formation of IVC Sigmoid to Rectal
Transition- SV3